test: add simple full test via identity channel

amodem/recv.py

@@ -242,8 +242,7 @@ def main(args):
 
     log.info('Running MODEM @ {:.1f} kbps'.format(modem.modem_bps / 1e3))
 
-    fd = sys.stdin
-    signal = stream.iread(fd)
+    signal = stream.iread(args.input)
     skipped = common.take(signal, args.skip)
     log.debug('Skipping first %.3f seconds', len(skipped) / float(modem.baud))
 
@@ -254,7 +253,7 @@ def main(args):
     bits = receive(signal, modem.freqs, gain=1.0/amplitude)
     try:
         for chunk in decode(bits):
-            sys.stdout.write(chunk)
+            args.output.write(chunk)
             size = size + len(chunk)
     except Exception:
         log.exception('Decoding failed')
@@ -283,6 +282,8 @@ if __name__ == '__main__':
     p = argparse.ArgumentParser()
     p.add_argument('--skip', type=int, default=100,
                    help='skip initial N samples, due to spurious spikes')
+    p.add_argument('-i', '--input', type=argparse.FileType('r'), default=sys.stdin)
+    p.add_argument('-o', '--output', type=argparse.FileType('w'), default=sys.stdout)
     args = p.parse_args()
     try:
         main(args)

amodem/send.py

@@ -85,29 +85,27 @@ def main(args):
     import ecc
     log.info('Running MODEM @ {:.1f} kbps'.format(modem.modem_bps / 1e3))
 
-    fd = sys.stdout
-
     # padding audio with silence
-    writer.write(fd, np.zeros(int(config.Fs * args.silence_start)))
+    writer.write(args.output, np.zeros(int(config.Fs * args.silence_start)))
 
-    start(fd, sym.carrier[config.carrier_index])
+    start(args.output, sym.carrier[config.carrier_index])
     for c in sym.carrier:
-        training(fd, c)
+        training(args.output, c)
     training_size = writer.offset
     log.info('%.3f seconds of training audio',
              training_size / wave.bytes_per_second)
 
-    reader = Reader(sys.stdin, 64 << 10)
+    reader = Reader(args.input, 64 << 10)
     data = itertools.chain.from_iterable(reader)
     encoded = itertools.chain.from_iterable(ecc.encode(data))
-    modulate(fd, bits=common.to_bits(encoded))
+    modulate(args.output, bits=common.to_bits(encoded))
 
     data_size = writer.offset - training_size
     log.info('%.3f seconds of data audio, for %.3f kB of data',
              data_size / wave.bytes_per_second, reader.total / 1e3)
 
     # padding audio with silence
-    writer.write(fd, np.zeros(int(config.Fs * args.silence_stop)))
+    writer.write(args.output, np.zeros(int(config.Fs * args.silence_stop)))
 
 if __name__ == '__main__':
     logging.basicConfig(level=logging.DEBUG,
@@ -117,5 +115,7 @@ if __name__ == '__main__':
     p = argparse.ArgumentParser()
     p.add_argument('--silence-start', type=float, default=1.0)
     p.add_argument('--silence-stop', type=float, default=1.0)
+    p.add_argument('-i', '--input', type=argparse.FileType('r'), default=sys.stdin)
+    p.add_argument('-o', '--output', type=argparse.FileType('w'), default=sys.stdout)
     args = p.parse_args()
     main(args)

amodem/test/test_common.py

@@ -45,3 +45,9 @@ def test_icapture():
         z.append(i)
     assert x == y
     assert x == z
+
+
+def test_dumps_loads():
+    x = np.array([.1, .4, .2, .6, .3, .5])
+    y = common.loads(common.dumps(x * 1j))
+    assert all(x == y)

amodem/test/test_full.py

@@ -0,0 +1,33 @@
+import os
+from cStringIO import StringIO
+
+import send
+import recv
+import common
+
+class Args(object):
+    def __init__(self, **kwargs):
+        self.__dict__.update(kwargs)
+
+def run(chan, size):
+    tx_data = os.urandom(size)
+    tx_audio = StringIO()
+    send.main(Args(silence_start=1, silence_stop=1, input=StringIO(tx_data), output=tx_audio))
+
+    data = tx_audio.getvalue()
+    data = common.loads(data)
+    data = chan(data)
+    data = common.dumps(data * 1j)
+    rx_audio = StringIO(data)
+
+    rx_data = StringIO()
+    recv.main(Args(skip=100, input=rx_audio, output=rx_data))
+    rx_data = rx_data.getvalue()
+
+    assert rx_data == tx_data
+
+def test_small():
+    run(chan=lambda x: x, size=1024)
+
+def test_large():
+    run(chan=lambda x: x, size=64 << 10)